Original Soundtracks (OST) are personally, my favorite part of a game. When an OST is memorable, it's the part of the game that you can go back to and relive story moments, characters, and gameplay mechanics. Because of that, OSTs are extremely important to me in a game, and I tend to listen to them a lot.
I love to listen to relaxing OSTs when I complete work, have calming drives, or just want to relax. Here's a short but hopefully great, list of my favorites!
1. Undertale
2. Deltarune
Fun Fact: Deltarune is Undertale's sequel.
3. Coffee Talk
There's also an "ambience" version of the soundtrack that has light rain and cars driving by and such, and that version is on YouTube and equally as stunning.
4. Professor Layton and the Unwound Future
All of the Professor Layton games OSTs are amazing, this one is simply my favorite.
5. Animal Crossing: New Leaf
Like Professor Layton, all of the Animal Crossing games have amazing songs, New Leaf is just the best one in my opinion.